DMSP 5D-3 F19 (USA 249) is a global weather observatory for the U.S. armed forces. The craft carries a sophisticated suite of weather instruments to observe virtually the entire planet twice daily. Data from DMSP satellites is used to create global weather forecasts that military commanders and strategic planners rely upon. The satellites can track weather systems by visible and infrared cloud-cover imagery, day and night, plus monitor ice and snow coverage, pollution and fires. The primary sensor, one of seven aboard, is the Operational Linescan Sensor, which collects visible and infrared cloud pictures in 1,800-mile [2,897-km] swaths covering the globe. The microwave sounder provides storm intensity measurements.